diff --git a/docs/source/apps/cct.rst b/docs/source/apps/cct.rst
index 7fb87b10ac..6230fb8631 100644
--- a/docs/source/apps/cct.rst
+++ b/docs/source/apps/cct.rst
@@ -57,6 +57,8 @@ performs transformation coordinate systems on a set of input points. The
 coordinate system transformation can include translation between projected
 and geographic coordinates as well as the application of datum shifts.
 
+Note however that unlike the :program:`proj`, angular input must be in decimal degrees.
+Any minutes and seconds given will be silently dropped.
 
 The following control parameters can appear in any order: